Apparatus for bonding and laying conductors

ABSTRACT

An apparatus is described for bonding and laying conductors by means of a multi-axial positioning unit in which the cable is guided in a laying tube and is advanced by a feed unit. The apparatus according to the invention is characterized by the combination of the following features: 
     the apparatus comprises a jaw gripper, of which the gripper jaws comprise, extending in the plane of the jaws, recesses which form the laying tube; 
     the feed unit is integrated into the gripper jaws and is reversible; 
     provided at the ends of the laying tube are shaping elements which center a contact as the cable is drawn into the laying tube.

An apparatus is described for bonding and laying conductors by means ofa multi-axial positioning unit, wherein the cable is guided in a layingtube and is advanced by a feed unit.

For some considerable time, no appropriate apparatus has been known forautomatic bonding and laying of conductors with so-called crimpedcontacts. Only pilot installations have become known in some isolatedinstances but they have not become established in industrial practice.

In the case of the pilot installations of Messrs. UNIMATION ANDVEKTRONICS, problems occur particularly in the storage of the cable withthe attached crimped contact and in handling the cable which isflexurally slack.

Practical solutions have only become known from applications filed bythese Applicants and then only for the manufacture of laced wiring loopswith `cut-and-clamp connectors`, using cable drums.

The invention is based on the problem of indicating a practicalapparatus for bonding and laying conductors by means of a multi-axialpositioning unit in which there are no limitations of any kind withregard to the cable contacts, i.e. an apparatus which makes it possiblenot only to produce laced wiring harnesses with so-called cut-and-clampconnectors but also to manufacture wiring harnesses for example withso-called crimped contacts. According to the invention, a solution tothis problem, together with its further developments, is characterisedin the Patent Claims.

Surprisingly, this problem is successfully resolved in that the premiseadopted is an apparatus such as that described in applications by thesame Applicants, in which the manufacture of cable harnesses using thecut-and-clamp technique stand to the fore and in that this genericapparatus is further developed by the combination of the followingfeatures:

the apparatus comprises a jaw gripper, of which the gripper jawscomprise, extending in the plane of the jaws, recesses which form thelaying tube;

the feed unit is integrated into the gripper jaws and is reversible;

provided at the ends of the laying tube are shaping elements whichcentre a contact as the cable is drawn into the laying tube.

Further developments of the invention are characterized in thesub-claims:

For example, according to claim 2, the laying tube may comprise awidened-open portion which serves to store the random cable. Thiswidened portion is preferably "pear-shaped".

Furthermore, according to claim 4, there are on both sides of thewidened portion a respective feed unit.

Furthermore, according to claim 5, there is upstream of the laying tubein the direction of feed of the cable a further unit with a further feedunit and a unit for reducing the cable to lengths, and in that the jawgripper is pivotable in respect to the further unit (claim 5).

According to claim 6, this further unit may in addition comprise a cableclamping unit.

Furthermore, the feed unit may comprise a friction wheel and a drivenwheel which can be applied in the direction of the friction wheel bymeans of a pressure-applying unit.

The invention will be described in greater detail hereinafter withreference to examples of embodiment and with no limitation of thegeneral index underlying the invention, reference being made to thedrawings, in which:

FIGS. 1a and 1b are different views of a first example of embodiment ofthe invention and

FIGS. 2a and 2b show different views of a second example of embodiment.

Both examples of embodiment have in common a tool changing flange 1 anda parallel jaw gripper 5.

In per se known manner, the tool changing flange 1 is the interfacebetween a handling or positioning arrangement, for example an industrialrobot, and the actual tool and it ensures transmission of the(electrical, pneumatic and/or hydraulic) energy and the transfer of thevarious control signals from the control arrangement to the tool or ofthe sensor signals from the tool to the control arrangement.

The parallel jaw gripper 5 comprises two gripper jaws 5' and 5" whichare articulated on an intermediate flange 51. Each gripper jawcomprises, extending at a right-angle to the direction of movement ofthe jaws, a recess 52' or 52" which form a laying tube 520, the diameterof which is greater than the diameter of the largest cable which is tobe laid.

In the case of the example of embodiment shown in FIGS. 1a and 1b, therecesses 52 comprise substantially centrally a "pear-shaped" widened-outportion 53, the function of which will be explained hereinafter. On bothsides of the widened-out portion 53 are cable feed units 54 (designated' and "), which each consist of a drive wheel 57 driven by a reversibleelectric motor, the drive wheel 57 being adapted to be pre-tensioned inthe direction of the laying tube by a pneumatic cylinder 58.

In the case of the example of embodiment shown in FIGS. 2a and 2b, onlyone feed unit 54 is provided and in which, as an example, a V-belt 59 isshown as the connection between the motor 56 and the drive wheel 57.

Furthermore, in the example of the embodiment shown in 2a and 2b, afurther unit is provided with a cable guide tube 20 which consists of acable clamping unit 2 with a clamping element 21, a further cable feedunit 3 which may likewise comprise elements 55 to 59, and alength-cutting unit 4 with a length-cutting element 42 adapted to beactuated for example by a pneumatic unit 41 and having a counter element43.

The cable clamping unit 2 serves to clamp securely a cable which is notshown, so that it cannot be withdrawn by the movement of the tool.

The length-cutting unit 4 serves to cut the cable at a clearly definedlocation, while the feed unit 3 serves to feed the cable in the furtherunit.

In the case of the example of embodiment shown in FIGS. 2a and 2b, theparallel jaw gripper 5 can by means of a hydraulic jack 7 be pivotedthrough at least 90° in respect of the further unit.

The ends of the laying tube 520 have in both embodiments (divisible)shaped elements 8 which permit the "centered" draw-in of a contact, forexample of a crimped contact. The shaped elements 8 can for example beexchanged for a dovetail guide so that by exchanging appropriate"contact-specific shaped elements", also wiring harnesses havingdifferent contact elements can be assembled. By an appropriate shapingof the shaped elements 8 which may be in particular project beyond thecontours of the grippers, it is also possible to equip complicatedmulti-pole plugs without collision problems.

Initially, a laying process will be described hereinafter, employing thetool shown in FIG. 1 and then using the tool shown in FIGS. 2a and 2b.

In this respect, with both tools, the adopted premise will be that of anindustrial robot, a tool magazine with tools, a laying board with layingaids and plug housings as well as an attaching machine of per se knownconstruction.

FIRST EXAMPLE OF EMBODIMENT

The robot changes the tool via the changing flange 1 from a magazine andpositions it in front of a cable feed unit of per se known construction.

When the parallel jaw gripper 5 is closed, the cable is introduced intothe laying tube 520 which is formed. By actuating the pneumatic cylinder58, the cable is clamped between the friction wheel 55' and the counterroller 57. When the motor 56" is not switched on, the cable is thussecuring in its position.

By means of the electric motor 56' shown on the right in the drawing butnot described in greater detail, the cable is laid into the store 57from the store tip. This takes place in that the pneumatic cylinder 58presses the driving roller 57 against the friction wheel 55 and theelectric motor 56 is switched on.

By reason of the pear-shaped form of the widened-out portion, the cablewhich is advanced comes to bear against the walls of the widened-outportion. When the desired length of cable is present in the tool, thecable is cut off in the cable preparation means, not shown.

The cable is then passed on sufficiently that a definite portion stillprotrudes from the tool.

Now, with the tool and the cable stored in the tool, the positioningunit moves to an insulating machine which insulates the two cable endswhich are projecting from the laying tube. The insulated cable ends arethen provided with contacts, particularly crimped contacts.

The two electric motors 56 of the feed units 54 are then switched on andthe two cable ends with the crimped contacts are drawn into the shapedelements 8 at the ends of the laying tube.

The robot now travels to the first plug housing and attaches thecentered contact. The contact is pushed in completely by the electricmotor which is disposed on this side. In order to ensure that thecontact has fully engaged the plug housing, the direction of rotation ofthe motor is reversed so that a tractive force is applied to the cable.For example, it can be recognised from the current input of the motorwhether or not the contact is fully engaged in the plug housing.

The robot now lays the cable in accordance with the path input into it.For laying, the tool can be tilted through 90° by the robot so that thelaying tube is at right-angles to the laying board.

During the laying process, the associated delivery mechanism is relaxedso that the cable is withdrawn from the storage means.

The process of attaching the second cable end then takes place asdescribed above.

Once both contacts have been joined, the gripper is opened so that thelaying tube opens along its longitudinal axis and releases the cable.

The robot can now pick up a new cable or change over to a new andequivalent tool in which a cable has already been drawn into the standbymagazine.

SECOND EXAMPLE OF EMBODIMENTS

Firstly, the robot changes the tool in which a cable is already presentin the cable shaft of the "further unit" and is being prevented by thecable clamping 2 from sliding out of the shaft.

Now the hydraulic jack of the cable feed unit 3 is actuated so that thedrive wheel is pressed against the friction wheel. By operation of theelectric motor, the cable is passed through the length-cutting unit intothe laying tube of the gripper 5. The diameter of the gripper tube issuch that the cable has clearance in the laying tube.

Once a definite portion of cable has been delivered, the front end ofthe cable reaches the feed unit in the parallel jaw gripper which pushesthe cable forwards sufficiently that a definite portion protrudes fromthe laying tube.

Then, the robot travels to an insulating and attaching machine whichprovides the projecting cable end with a contact. By reversing theelectric motor, the contact is drawn into and centred in the shapedelement.

The robot then travels to a first plug housing and attaches the centredcontact. The electric motor disposed on this side fully inserts thecontact. In order to ensure that the contact is fully engaged in theplug housing, the direction of rotation of the motor is reversed so thata tractive force is exerted on the cable. For example, it can be seenfrom the current input of the motor that the contact is fully engaged inthe plug housing.

The insertion process can take place in both the horizontal and verticalpositions of the laying process. It is possible thereby to "tilt" thegripper accordingly in relation to the further unit.

The robot now lays the cable in accordance with the path input into it.While this is happening, the cable is "pulled through" the tool.

After the laying stage, the cable is securely clamped by the clampingmechanism 2 and is cut to length by the device 3.

The cable is then secured in its position in the gripper by the feedunit 4 and is advanced sufficiently that a specific portion projectsfrom the laying tube. The cable is now provided with a contact asdescribed previously; this contact is then again "centred" by reversalof the electric motor.

The attachment or joining process when then follows is likewiseconcluded with a "pull test". When the connection process is completed,the gripper is opened and the cable is thus released.

The next cable can then be laid in the same way.

I claim:
 1. An apparatus for the bonding and laying of conductors bymeans of a multi-axial positioning unit in which the cable is guided ina laying tube and is advanced by a feed unit, characterised by thecombination of the following features:the apparatus comprises a jawgripper, of which the gripper jaws comprise, extending in the plane ofthe jaws, recesses which form the laying tube; the feed unit isintegrated into the gripper jaws and is reversible; provided at the endsof the laying tube are shaping elements which centre a contact as thecable is drawn into the laying tube.
 2. An apparatus according to claim1, characterised in that the laying tube comprises a widened-out portionwhich serves to store the random cable material.
 3. An apparatusaccording to claim 2, characterised in that the widened-out portion ispear-shaped.
 4. An apparatus according to claim 2, characterised in thata feed unit is provided on both sides of the widened-out portion.
 5. Anapparatus according to claim 1, characterised in that upstream of thelaying tube, in the direction of cable feed, there is a further unitwith a further feed unit and a unit for reducing cable to lengths and inthat the jaw gripper is pivotable in relation to the further unit.
 6. Anapparatus according to claim 5, characterised in that the further unitadditionally comprises a cable clamping unit.
 7. An apparatus accordingto any of claims 1 to 6, characterised in that the feed units comprise afriction wheel and a driven wheel which can be pre-tensioned in thedirection of the friction wheel by means of a pressure-applying unit. 8.An apparatus according to claim 7, characterised in that thepressure-applying unit is a pneumatic cylinder.
 9. An apparatusaccording to claim 7, characterised in that a reversible electric motordrives the driven wheel.
 10. An apparatus according to any of claims 1to 6, characterised in that the jaw gripper is a parallel jaw gripper.11. An apparatus according to any of claims 1 to 6, characterised inthat in the ends of the laying tube formed by the gripper jaws there areshaped elements for centering the contacts.
 12. An apparatus accordingto claim 11, characterised in that the shaped elements areinterchangeable.
 13. An apparatus according to claim 10, characterisedin that at the ends of the laying tube formed by the gripper jaws thereare shaped elements for centering the contacts.